There are many reasons to encrypt files — even on a system that is
well maintained and comparatively secure. The files may highly
sensitive, contain personal information that you don't want to share
with anyone, or be backed up to some variety of online storage where you'd prefer it be extra secure.
Fortunately,
commands for reliably encrypting files on Linux systems are easy to
come by and quite versatile. One of the most popular is gpg.
gpg vs pgp and OpenPGP
Used both to encrypt files in place and prepare them to be sent securely over the Internet, gpg is related to, but not the same as, pgp and OpenPGP. While gpg is based on the OpenPGP standards established by the IETF, it is — unlike pgp — open source. Here's the rundown:
OpenPGP is the IETF-approved standard that defines encryption technology that uses processes that are interoperable with PGP.
pgp is Symantec's proprietary encryption solution.
gpg adheres to the OpenPGP standard and provides an interface that allows users to easily encrypt their files.
Using gpg for symmetric encryption
Symmetric
encryption means that you use the same key to both encrypt and decrypt a
file. To encrypt a file with minimal effort, you could use a command
like this:
$ gpg2 --symmetric myfile
This command will leave you with two files — myfile and
myfile.gpg. Once you verify that the encrypted version of your original
file has been created, you can use the shred command to
securely remove the original file in a way that prevents it from being
scraped off the disk with some disk recovery tool. During the encryption
process, this command will also open up a tool on your desktop to
prompt you twice to enter your passphrase. So, you have to be working on
the desktop.
To do this kind of thing when you're not
working on the console, you can avoid having gpg trying to open up a GUI
tool to prompt for your passphrase by supplying it on the command. In
this case, you might use a command like this:
NOTE: It's bad practice to store your passphrase in clear text -- even in your command history file, so be careful if you do this.
Using public and private keys
To
use gpg for creating files that you want to share with other people,
it's generally best to use private/public keys. To share a file with a
particular person, you encrypt it using their public key. In that case,
that person is (presumably) the only one who can decrypt it. If you
encrypt a file with your own public key, you’re the only one who can
decrypt it.
To generate your public and private key set with gpg, you would use a command like this:
$ gpg --gen-key
Note that this command also requires that you be working on the
console (GUI), not through an ssh session. The command is going to
require that you produce some activity while your keys are bring
generated — such typing or as moving your mouse cursor around the screen
— to provide random data to the encryption process. It will also ask
you to supply some information, such as your full name and the email
address to be used for the key.
To encrypt a file for a particular
recipient, you need to use a command that includes the --recipient
argument to specify the recipient's public key.
It's interesting to note that while the private and public keys
are linked (generated in a single operation), either key could play
either role.
If you encrypt with the public key, you could decrypt with the private key
If you encrypt with the private key, you could decrypt with a public key
Convention dictates, however, that private keys are kept private.
We also haven't looked at how public keys are used for authenticating senders.
Other command options
The
gpg command offers many other options, as well. For example, if you
prefer to use other than the default AES-128 encryption algorithm, you
can specify the one you want to use with a command like this:
$ gpg --cipher-algo AES256 --symmetric myfile
You can list your keys with this command:
$ gpg --list-keys
Wrap-up
While gpg commands can become
quite complicated, the things you're likely to do routinely can be
accomplished without a lot of effort.
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Traceroute command is well known networking utility using which we
can determine the number of hops between source & destination of a
network packet. Not only does it show the number of hops, we will also
get the information regarding the path/servers it goes through.
Traceroute
command is well known networking utility using which we can determine
the number of hops between source & destination of a network
packet.Usually the traceroute command in Linux is used to determine the
data loss occurring in the network, as each hop shows the network
address of the router or server it passes, we can know at which server
or router our packet was lost. Recommended Read : Monitoring network bandwidth with iftop command Also Read :Let’s discuss some examples of SED command
In
this tutorial, we are going to discuss how we can install traceroute
command in Linux & also how to use it to troubleshoot the network.
Install Traceroute command in Linux
Traceroute
command comes pre-installed on many Linux distributions but if that’s
not the case with you, you can install it using one of the following
commands,
CentOS/RHEL/Oracle Linux/Amazon Linux # yum install traceroute Ubuntu/Debian/Mint # apt-get install traceroute Fedora # dnf install traceroute
If
using sudo user, than add sudo before the installation command. Now
let’s discuss the syntax for using traceroute command in Linux, Syntax # traceroute [option] destination
Now let’s discuss some examples for using traceroute command in Linux.
Examples of traceroute command in Linux
1- Check route for a server
To
simply get the route taken by a network packet to get to a certain
server or website (for example google), run the following command from
the terminal, $ traceroute google.com
We can run the traceroute against an IP address of a server or website, $ traceroute 8.8.8.8
As output we will get the following result,
Now output shows the following info, – First line after the command shows the destination IP address (blacked out in the screenshot), – Next line after that & all the rest lines shows the hops, their IP address, response time etc. By default, traceroute command in linux sends 3 packets for each hop, hence we get three response time on each line. – Sometimes we might get a ‘*’ in place of response time, that shows that we were unable to get a response for that request.
Both examples mentioned above uses IPV4, but to send a query for IPv6 we can use following example as reference, $ traceroute -6 ipv6.google.com
This
example itself is sufficient enough for network troubleshooting but we
can also change the default values of traceroute command to satisfy our
requirements. 2- Configure TTL for traceroute
By default the TTL value for traceroute command is 1, but we can configure it to some other value using option ‘f’, for example $ traceroute -f 5 google.com 3- Configure the response wait time
The response wait time can also be changed to a value other than the default value using the option ‘w’, $ traceroute -w 0.5 google.com 4- Configure number of queries
Per
hop, traceroute sends 3 queries/packets & provide 3 round trip
time. Now let’s suppose we want to send 4 packets per hop, we can do it
using option ‘q’, $ traceroute -q 4 google.com 5- Disable IP, Hostname mapping
Option ‘n’ can be used with traceroute command to disable IP address & hostname mapping, $ traceroute -n google.com 6- Configure network interface for traceroute
If
using multiple network interfaces on Linux system, we can also
configure traceroute to use only a particular interface using option
‘i’, $ traceroute -i enp2s0 google.com
We
now end this tutorial on using traceroute command in Linux, we have
only discussed some of the commonly used options of traceroute. There
are many more options that can be used with traceroute command, refer to
MAN pages for all the available options for traceroute command in
Linux.
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Google Drive is a cloud-based file storage that
allows you store your files on Google Servers, share files with other
users and also synchronize the files among various devices including
your computer, mobile phone, tablets etc. To access Google Drive you
only need to have Gmail account and even offers 15GB of free storage space.
Launched in 2012, Google Drive can be easily accessed in Windows
system, Android and iOS but Google is yet to announce an official client
for Linux desktops to access your files in Google Drive. But there may
tools available in Linux that allows you to easily access Google Drive.
In this article, we are going to look for different ways to access
Google Drive on Linux Desktop.
Insync
When it comes to providing complete access to Google Drive from Linux, Insync
is one of the best clients available to come with a lot of features and
provides you options to get anything you need from Google Drive. It
also supports multiple Google Drive accounts, notification features etc.
It is supported in many of the popular Linux distributions and the
installation process is also pretty straightforward and simple. It also
comes with an attractive GUI to enable easy access of Google Drive and
its features. A command line interface is also supported.
But the main problem it is available for free only for 15 days and
you need to pay for using the software after 15 days. And it will cost
around $29 for a single user account and separate packages available for
multiple account usage. And if you willing to pay some money, we can
definitely say that Insync is the best Google drive client available for
Linux Desktop.
Access Google Drive from Ubuntu Desktop
Unlike Windows and MacOS, accessing Google Drive from a Ubuntu
desktop is slightly different. Let’s take a look at how to access the
Google Drive from your Ubuntu Desktop
In your Ubuntu Desktop, go to Settings –> Online Accounts
In Online Accounts you can see all your various accounts listed. Click the “Add” button to add your Google account
Now select Google from the list and provide your user credentials for your Google Account
Once you’ve provided your username and password, it will ask you ALLOW for permissions, just click “ALLOW“
In the next window, you can see option to enable/disable various
Google features including Mail, Photos, Files, Documents, Calendar,
Contacts, Chat etc.
Click ON to enable the required functions
Your Google Drive is ready for use now
Mount your Google Drive by opening the Files Window and double-click on your Google account to mount it in your system
You can add, remove any files and folder to your local drive to your Google Drive or vice versa.
You can also see a separate drive icon appearing on your desktop for your Google Drive
OverGrive
OverGrive is another interesting Linux desktop client that lets you
access most of the features of Google Drive and the only exceptions that
there is no symlink support provided. The GUI is pretty much simple and
easy to navigate and the installation is also straightforward and
simple. OverGrive is supported in all major Linux distributions and is
also available in various languages as well. But OverGrive is not
available for free, but when you compare the price with Insync, you can
get OverGrive for less than $5.
Rclone
Rclone is another Google Drive client but a command line program that
allows you to manage your files in your Google drive and sync files
between various other cloud storage devices like Amazon S3, Dropbox,
OneDrive etc. The installation is very simple and there is a descriptive
installation guide and usage manual available in their official
website. The main aspect about Rclone is that is available completely
for free. And if you are fan of command line interfaces, then you will
certainly like this Google Drive client.
Conclusion
It is certainly disappointing why Google has not come up with an
official Google Drive client for Linux even after it was launched for
Windows and iOS about 6 years before. But until they launch one, if you
are looking to use Google Drive from your Linux desktop, then you
certainly need to use any one of these clients to access Google Drive.
Please post your comments and suggestions in the comments section and
we’ll be happy to revert back at the earliest.
